title: Ethnicity, body mass, and genome-wide data.
abstract: This article combines social and genetic epidemiology to examine the influence of self-reported ethnicity on body mass index (BMI) among a sample of adolescents and young adults. We use genetic information from more than 5,000 single nucleotide polymorphisms in combination with principal components analysis to characterize population ancestry of individuals in this study. We show that non-Hispanic white and Mexican-American respondents differ significantly with respect to BMI and differ on the first principal component from the genetic data. This first component is positively associated with BMI and accounts for roughly 3% of the genetic variance in our sample. However, after controlling for this genetic measure, the observed ethnic differences in BMI remain large and statistically significant. This study demonstrates a parsimonious method to adjust for genetic differences among individual respondents that may contribute to observed differences in outcomes. In this case, adjusting for genetic background has no bearing on the influence of self-identified ethnicity.
authors.affiliation: Institute of Behavioral Science and University of Colorado Population Center, University of Colorado, Boulder, Colorado 80309-0483, USA. boardman@colorado.edu
authors.forename: Jason D
authors.initials: JD
authors.lastname: Boardman
authors.forename: Casey L
authors.initials: CL
authors.lastname: Blalock
authors.forename: Robin P
authors.initials: RP
authors.lastname: Corley
authors.forename: Michael C
authors.initials: MC
authors.lastname: Stallings
authors.forename: Benjamin W
authors.initials: BW
authors.lastname: Domingue
authors.forename: Matthew B
authors.initials: MB
authors.lastname: Mcqueen
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Crowley
authors.forename: John K
authors.initials: JK
authors.lastname: Hewitt
authors.forename: Ying
authors.initials: Y
authors.lastname: Lu
authors.forename: Samuel H
authors.initials: SH
authors.lastname: Field
mesh_terms: D000293:Adolescent; D015992:Body Mass Index; D001835:Body Weight / Q000208:ethnology* / Q000235:genetics*; D003120:Colorado / Q000453:epidemiology; D005260:Female; D055106:Genome-Wide Association Study; D006801:Humans; D008297:Male; D009765:Obesity / Q000208:ethnology* / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D025341:Principal Component Analysis; D012307:Risk Factors; D055815:Young Adult